Frank o



F. '0. WELLS.

LIMIT GAGE.

APPLICATION FILED FEB. 24. I916.

1 ,30'1426} Patented J1me 24,1919.

- l/VVE/VTOR Fran 0 We;

FRANK O. WELLS, or GREENFIELD, MASSACHUSETTS, AND DIE CORPORATION, OF GREENFIELD,

ASSIGNOR T0 GREENFIELD TAP MASSACHSUSETTS.

LmIT-GAGE.

Specification of Letters latent.

Patented June 24, 1919.

Application filed February 24, 1916. Serial No. 80,206.

siding at Greenfield, in the county of Franklin and State of Massachusetts, have invented new and useful Improvements 1n Limit-Gages, of which the following is a specification.

This invention relates to limit-gages for testing the outside dimensions of work, and has for its primary object theprovision of a single clamping screw and clamp proper for securing the points or anvils of each pair in set position.

A further object is to provide means whereby the gage is rendered extremelysensitive in Operation.

'To these ends the invention consists the construction and arrangement. of parts set forth more fully hereinafter in the specification and'claims and illustrated in the accompanying drawings, in which:

gigure 1 is a side elevation of the gage; an

Fig. 2 is a sectional view on line 2-2 of Fig. 1.

Referring to the drawings, 1 designates the substantially yokehaped frame of the gage, which is provided medially with an outwardly projecting finger ring 2. The arms of the frame are provided terminally with pairs of alining bosses 3 in which the points or anvils 4 and 5 are mounted. The outermost eoacting points 5- are farther separated than the points 4 and thus :ve the maximum limit, whereas the latter a 0rd the minimum limit. This arrangement is well known so it should require'no further explanation. The points 4 and 5 of each pair are backed up by adjusting screws 5 and are adapted to be secured fixedly in set position within the bosses of the corresponding arm of the frame by means of a single clamp bar 6 and the screw 7 associated therewith.

The frame is provided with a socket 8 in each arm which opens into the point sockets S) of the bosses 3. The clamp bar 6 for each pair of points is adapted to fit snugly within the corresponding sockets 8 so as to bridge the gap between the bosses, and has its ends beveled as at 10 to provide jaws for even engagement with the longitudinally extending flat surfaces 10 of the points i and 5. The screw 7 is rotatably mounted within an opening in the web of the frame 1 between bosses and is in threaded engagement with a medial opening in the clamp bar. Therefore, when the screw is tightened the terminal jaws of the clamp bar will be caused to grip the said points securely to prevent displacement of the same after they have been properly set. Owing to the provision of the flat surfaces 10 the points cannot turn in their sockets during axial adjustment. The outer ends of the point sockets 9 are then sealed by means of sealing wax or the like, such as that indicated by the numeral 11 in Fig. 1.

Owing to the specific construction of the clamping device for the points of the gage, the device is extremely compact and is com- .posed of a minimum number of parts,'so that it may be manufactured economically and is capable of being adjusted or set readily and With little effort.

In the use of the gage, the person using the same inserts a finger through the ring 2 so as to suspend the gage therefrom as apivot. It is then applied to a master piece of work, such as a cylinder, or thelike of a size corresponding .to' the adjustment of the gage points by lowering the same into contact therewith. Then, it is applied to the new piece of work' to be tested, in the same manner. An expert operator can detect with remarkable accuracy any difference in the sizes, from the difference in feel. A gage which has to be gripped between the fingers in a substantially fixed manner during use is not capable of such sensitive testing. This is an important feature of the invention.

Having thus described the invention, what it is desired to claim and to secure by Letters-Patent, is:

1. A limit-gage comprising a frame having pairs of correlated contact points adjustably mounted therein, a single clamping member for each pair of contact points having portions thereof engaged with the corresponding contact points, and means for actuating the said clamping member.

2. A limit-gage comprising a frame having pairs of alining sockets therein, correlated contact points adjustably mounted within the said sockets, adjusting screws provided within the sockets to back-up the respective contact points, a single clamping member for each pair of contact points having portions thereof engaged with the corvided Within the respective sockets to backh responding points, and means. for actuating the clamplng member.

3. A limit-gage comprising a frame having pairs of alining sockets thereln, correlated contact points adjustably mounted within the said sockets and having fiat longitudinal surfaces, adjusting screws proup the contact points therein, a single clamping member for each pair of contact points having flat surfaces adapted to contact wlth the said fiat surfaces of the corresponding contact points, and means for actuating the clamping member.

4. A limit-gage comprising a frame having pairs of alining sockets therein and-an" additional socket communicating with both 'of the first-named sockets of each pair, correlated contact points adjustably mounted within the first-named sockets, a single clamping member mounted within each of the'said additional sockets for engagement with the corresponding contact points, and means for actuating the clamping member.

5. A limit-gage comprising a frame having pairs of correlated contact points adjustably' mounted therein, a single clamping bar for each pair of contact points having the ends thereof engaged with the corresponding contact points, and a clamping screw mounted within the frame and engaged medially with each clamping bar.

6. A limit gage comprising a frame, a plurality of contact points, one contact point having a generally cylindrical shank, said shank being cut away along its length to provide a flat surface, a clamping member having a flat surface engaging the fiat surface on the shank, and means for forcing said two fiat surfaces together.

7. A limit gage comprising a frame, a

plurality of contact points, one contact point having a generally cylindrical shank, said shank being cut away along its length to provide a flat surface, a clamping member having a fiat surface engaging the flat surface on the shank, the clamping member comprising an elongated block with its length arranged substantially perpendicular gether.

. 8. A limit gage comprising. a frame, a plurality of contact points, one contact point aving a generally cylindrical shank, said shank bein cut away along its length to provide a at surface, a clamping member having a flat surface engaging the flat surface on the shank, the clamping member comprising an elongated, block with its length arranged substantially perpendicular to the axis of the shank, the said clamping member having a beveled end forming said flat surface of the clamping member, and a clamping screw threaded into the clamping member.

'9. A limit gage comprising a frame, a

having a generally cylindrical shank, said shank being cut away along its length to provide a flat surface, a clamping member having a flat surface engaging the flat surface on the shank, the clamping member comprising an elongated block with its length arranged substantially perpendicular to the axis of the shank, the said clamping member having a beveled end forming said flat surface of the clamping member, and a clamping screw threaded into the clamping member and arranged substantially perpendicular to both the clamping member and said shank.

10. A limit gage comprising a frame having a pair of correlated flattened cylindrical contact points adjustable thereon, a single clamping member having beveled surfaces 

